Wrong-site surgery rare, major injuries even more so

Insurance records suggest that wrong-site surgery is extremely rare and major injury from it even rarer, according to a study supported by the Agency for Healthcare Research and Quality.

Researchers led by Mary R. Kwaan, MD, MPH, a physician and researcher at Brigham and Women's Hospital and Harvard School of Public Health in Boston, estimate that a wrong-site surgery serious enough to result in a report to insurance risk managers or in a lawsuit would occur approximately once every five to 10 years at a single large hospital.1

The study assessed all wrong-site surgeries reported to a large medical malpractice insurer between 1985 and 2004 and found that the number of wrong-site surgeries conducted on limbs or organs other than the spine occurred once in every 112,994 operations. Forty cases of wrong-site surgery were identified among 1,153 malpractice claims and 259 instances of insurance loss related to surgical care. Twenty-five of the cases were nonspine wrong-site surgeries, with the remainder involving surgery of the spine.

AHRQ director Carolyn M. Clancy, MD, says the good news is that wrong-site surgery is extremely rare, and major injury from it even less common. "The less good news is that although site-verification protocols offer some protection against such errors, they are not foolproof," she says. "We have a lot more to do to ensure that wrong-site surgery never happens."

The study examined site-verification protocols at 25 hospitals as a means to prevent wrong-site surgery from occurring. The site-verification protocols included marking the operative site, a pre-operative verification process by the surgeon and one other health care staff member, and informed consent from the patient with specification of the site of the surgery. The study found that simplicity and avoidance of excessive redundancy are the key features of successful site-verification protocols.

Available medical records for 13 of the 25 nonspine wrong-site surgery cases show that injury was temporary and minor in 10 of the cases. Researchers conclude that following the Joint Commission on Accreditation of Healthcare Organizations' Universal Protocol for Preventing Wrong Site, Wrong Procedure, Wrong Person Surgery might have prevented eight of the cases.


1. Kwaan MR, Studdert DM, Zinner MJ, et al. Incidence, patterns, and prevention of wrong-site surgery. Arch Surg 2006; 141:353-357.